This is an all-new type of holder for 4-lb. salt and mineral blocks. It's constructed of heavy-duty polyethylene plastic that won't rust or corrode. Wrap-around style provides more protection for the corners of the block than wire holders do. Pre-drilled holes allow easy mounting almost any flat or vertical surface such as a wall or fence rail (mounting hardware not included). Measures 3.75 inch long by 3.5 inch wide by 5 inch high, holds one 4-lb. salt or mineral block.